Separation of allyl alcohol from wood spirits residue



Patented Oct. 17, 1939 UNITED STATES PATENT OFFICE SEPARATION OF ALLYLALCOHOL FROM WOOD SPIRITS RESIDUE Edgar C. Britton and Gerald H.Coleman, Midland, Mich., assignors to The Dow Chemical Company, Midland,Mich., a corporation of Michigan No Drawing. Application February 11,1937, Serial No. 125,270

6 Claims. (Cl. 260-640) This invention relates to a method for recoverbeheated gradually to 55-75 C. to distill the aling allyl alcohol fromwood spirits residue. lyl chloride therefrom. The removal of allyl Inthe usual process for making wood alcohol chloride during such heatingmay be facilitated there is obtained from the distillation of crude byadding slowly a high-boiling acid, e. g. sulmethanol a residuecontaining 5-40 per cent by furic acid, to the mixture. According toanother 5 Weight of allyl alcohol and in addition water, procedure, woodspirits residue is maintained at unrecovered methanol, n-propanol,n-amyl alcoor below the temperature at which the said resihol, acetone,and various other compounds. Such due refluxes, preferably at about 75C., and gasresidue is commonly known, and herein referred eous oraqueous hydrogen chloride added, where- .0 rto as wood spirits residue.Due to the fact by the allyl chloride distills from the mixture as lothat n-propanol and certain other substances it is formed. The crudeallyl chloride produced present in such residue tend to distill alongwith by any of the above procedures may be rendered allyl alcohol, it isimpossible to separate the lat- 90-100 per cent pure by a singleredistillation. ter from wood spirits residue by fractional dis-Hydrolysis of the allyl chloride to allyl alcohol ..tillation. may becarried out by heating the allyl chloride 1L1? We have discovered thatwood spirits residue with 10-30 times its weight of water, preferablymay be treated with hydrogen chloride in such in the presence of analkaline catalyst, e. g. way that the allyl alcohol is selectivelyattacked 0.5-1.0 chemical equivalent of sodium hydroxide, and convertedto allyl chloride, which may readlime, or sodium carbonate, etc., permol of allyl Z0 ily be removed from the otherwise unchanged chloride. Inthe presence of such alkaline cata- 20..

wood spirits residue. We have also found that lyst the reaction may becarried out at atmosthe allyl chloride may be hydrolyzed toregenerpheric. pressure and at temperatures between 40 ate the allylalcohol, so that by such chemical and 70 C. in -40 hours; but in orderto reduce treatment the allyl alcohol in the original resithe timerequired it is preferable to heat the hydue may be recovered in goodyield and pure drolysis mixture in a suitable closed vessel under 25form. The reactions involved may be represuper-atmospheric pressure at100-150 C. for sented by the following equations: 3-15 hours. Inaddition to allyl alcohol, some diallyl ether may be formed by thehydrolysis. The (1) CH2 CH CH2OH+HI}; CH aqueous hydrolysis mixture maybe distilled, the

allyl alcohol usually coming over as a mixture 30,

(2) CH2=CH-CH2C1+H20 with water and diallyl ether. Thismixture mayCH2=CHCH20H+HC1 be dried, e. g. with potassium carbonate, and the Theinvention, then consists in the method here- 31 2 319 separated fromdiallyl ether by 1s 1 a mu. g g gg i g g jg and partlcularly pomted Thefollowing examples are illustrative, but are 36.

The pr f r ntial reaction between hydrogen not to be construed aslimiting the invention: chloride and the allyl alcohol in the presenceof Example 1 the other constituents in wood spirits residue proceedssatisfactorily in the absence of a catalyst.

40 However, to shorten the time required; improve the yield of allylchloride, and minimize formation of by-products, it is advantageous toemploy a catalyst, such as a copper-containing salt, e. g. cuprouschloride, cupric chloride, cupric sulfate, cupnc mtrai'ie or mlxtures ofsame' pleted, the reaction mixture was heated to 75 C. The reactlonbetween Pydrogen q t in order to distill any remaining allyl chloride.

the allyl alcohol present in wood spirits res1due The crude allylchloride distillate was washed may be carried out in Vanous Ways-According with water, dried over anhydrous magnesium sul- Procedure,gasems or 29 hydmgen fate, and then fractionally distilled. 312 g. of 95chloride is added to wood sp1r1ts res1due at or per cent any} chloridewas obtained.

slightly below room temperature. The mixture is allowed to stand untilan oil layer separates; Example? this layer is removed and the allylchloride dis- A mixture of 240 lbs. of wood spirits residue tilledtherefrom. The entire mixture of wood (31 per cent allyl alcohol), 375lbs. of 34 per cent spirits residue and hydrogen chloride may alsoconcentrated aqueous hydrochloric acid, and 1.12

5.0 g. of cupric chloride was dissolved in 880 g. of wood spiritsresidue (containing approximately 31 per cent by weight of allylalcohol), the solution heated to 55-65 C., and 340 g. of gaseoushydrogen chloride passed in slowly. Allyl chloride distilled from themixture as it was formed. When addition of hydrogen chloride was com- 45lbs. of cupric chloride was warmed to 40 C., whereupon 114 lbs. of crudeallyl chloride was distilled from said mixture at a rate of about 12lbs. per hour. The distillate was washed with water, dried by passingthrough a bottle filled with flake calcium chloride, and fractionallydistilled. 78.5 lbs. of 92.6 per cent allyl chloride was obtained.

Example 3 A mixture of 44 g. of wood spirits residue (31 per cent allylalcohol), '75 cc. of hydrochloric acid (sp. gr. 1.19), and 1.0 g.cuprous chloride was slowly heated to C. During heating of the mixture,24.0 g. of concentrated H2804 was added gradually and allyl chloride waspermitted to distill as it was formed. The crude allyl chloride productwas redistilled, whereby 15.8 g. of per cent allylchloride was obtained.

Example 4 A mixture of 5.82 mols of allyl chloride, 3.06 mols of calciumhydroxide and 123 mols of water was heated in a bomb at a temperature ofapproximately C. for 4 hours. After such heating allyl alcohol, diallylether and some water were distilled from the mixture. This distillatewas dried with potassium carbonate and fractionally distilled, whereby4.85 mols of allyl alcohol and 0.23 mol of diallyl ether were separatedas substantially pure compounds.

Example 5 0.5 mol of allyl chloride, 0.5 mol of sodium hydroxide and13.9 mols of water were heated for invention may be employed instead ofthe one explained, change being made as regards the method hereindisclosed, provided the step or steps stated by any of the followingclaims or the equivalent of such stated step or steps be employed.

We, therefore, particularly point out and distinctly claim as ourinvention:

1. The method of recovering allyl alcohol from wood spirits residuewhich comprises treating the latter with hydrogen chloride at atemperature not above the boiling point of the residue, whereby theallyl alcohol present in said residue is preferentially reacted uponforming allyl chloride as substantially the only aliphatic chlorideproduct, separating the allyl chloride and hydrolyzing the same to allylalcohol.

2. The method of recovering allyl alcohol from wood spirits residuewhich comprises treating the latter with hydrogen chloride at atemperature below 75 C., whereby the allyl alcohol present in saidresidue is preferentially reacted upon forming allyl chloride assubstantially the only aliphaticchloride product, distilling theresulting mixture to separate the allyl chloride therefrom, and heatingthe latter with an aqueous alkali solution to form allyl alcohol.

3. The methodwhich comprises treating wood spirits residue with hydrogenchloride at ternperature not above the boiling point of the residue,whereby the allyl alcohol present in said residue is preferentiallyreacted upon forming allyl chloride as substantially the only aliphaticchloride product, and separating the allyl chloride.

4.. The method which comprises treating wood spirits residue withhydrogen chloride at a temperature below 75 C. in the presence of acatalyst essentially comprising copper, whereby the allyl alcoholpresent in said residue is preferentially reacted upon forming allylchloride as substantially the only aliphatic chloride product, andseparating the allyl chloride.

5. The method which comprises treating wood spirits residue withhydrogen chloride at a temperature below 75 0., whereby the allylalcohol present in said residue is preferentially reacted upon formingallyl chloride as substantially the only aliphatic chloride product, anddistilling the resulting mixture to separate the allyl chloride.

6. The method which comprises heating wood spirits residue at atemperature not above its boiling point and passing gaseous hydrogenchloride into the heated residue, whereby the allyl alcohol present insaid residue is preferentially reacted upon forming allyl chloride assubstantially the only aliphatic chloride product, and distilling theallyl chloride from the mixture as it is formed.

EDGAR C. BRITTON. GERALD H. COLEMAN.

